Design a plan of a town that includes
Two sets of streets that are perpendicular .
One street that intersects another street to form an obtuse angles .
An ice cream parlour in the shape of an equilateral triangle .
A pool that is in the shape of an isosceles triangle .
A post office in the shape of trapezoid on a set of parallel streets .
A library in the shape of a quadrilateral at perpendicular intersection.